When one or more queries concurrently access a database index page, database systems typically implement latches to ensure data integrity. But latches can induce resource contention when multiple queries attempt to concurrently access the same page, which may result in severely degraded performance and increased execution time of the queries. Conventionally, latches may cause page-level contention because update queries and read queries block each other from accessing the same page. Additionally, when a query makes updates (e.g., inserts, updates, or deletes records) to the database page, that query acquires an exclusive latch that may prevent other queries from either reading or writing to the page.
In the drawings, like reference numbers generally indicate identical or similar elements. Additionally, generally, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears.